Clearing



Jan- 31, 1956 E. A. DAvls 2,733,011

v CLEARING MECHANISM Filed Nov. 17, 1952 2 Sheets-Sheet 2 ELWOOD A. DAVIS ATTORNEY nited States Patent Ofl 2,733,011 CLEARING MECHANIS'M Elwood A. Davis, Hayward, Calif., assignor to Friden Calculating Machine Co., Inet, a corporation of Callfornia Application November 17, 1952, Serial No. 320,991 6 Claims. (Cl. 235-144) This invention relates tov calculating machines and particularly to a mechanism adapted to clear the registers m any ordinal position of the carriage, in a machine of the type disclosed by the patent to Friden, No. 2,229,889, issued January 28, 1941.

A primary object of the present invention is to provide a clearing mechanism for a machine of the type described, which mechanism is operable in any ordinal position of the carriage.

Another primary object l' the present invention is to provide a clearing mechanism similar to that disclosed in the patent to Friden, No. 2,310,281 of February 9, 1943, but adapted to operate in any carriage position and to operate a single time only.

Another object of the present invention is to provide an improved register clearing mechanism operated in a single cycle and thereafter lpositively disengaged.

Another object of the present invention is to provide a clearing mechanism particularly adapted for use in connection with a back-transfer mechanism such as that shown in the copending application of Grant C. Ellerbeck, S. N. 225,733, tiled May 1l, 1951.

These, and other, objects of the invention will be apparent from the specication and claims which follow.

The description will be more readily understood by a reference to the drawings in which: v l I Fig. l isa rear view of a conventional Friden calculating machine with the present invention incorporated therein.

Fig. 2 is a longitudinal cross-sectional view of thecl'earing control mechanism associated with the present invention.

It will be understood that the present invention can be associated with various types of calculating machines, but is shown and described for purposes of exempliiication in connection with a conventional Friden calculating machine, such as those manufactured under the Friden patents above mentioned. In such a machine the operating mechanism, such as the selection mechanism and the actuators, is supported in a frame which includes the left and right frame plates and 11. Such mechanisms form no part of the present inventiomand therefore will not be described. It sulices to note that a shiftable carriage 12 is supported on the frame for transverse shifting movement in order to enable the various orders of the accumulator register to be aligned 'with various orders of the selection and actuating mechanism. The accumulator register comprises a plurality lof ordinally .arranged dials 13 and is supported in the shiftable carriage l2'. The register dials 13 are mounted upon their respective dial shafts 1,4 which are journalled in the carriage frame. Values from the selection mechanism are entered into the register dials 13 as described in said Patent No. 2,229,889. lt is occasionally necessary to zeroize, or clear, these dials in order to initiate a new calculation, and for that purpose the dials 13 can be cleared by a conventional clearing mechanism comprising a transversely shiftable clear rack 15 which is associated with, and operates upon, mutilated 2,733,011 Patented Jan. 3l, 1956 clear' gears 16 mounted on the respective accumulator dial shafts 14. As explained in said patents, the shifting of said rack I5 returns every dial and dial shaft which are angularly positioned away from their O position to O, whereupon the dial shafts are locked against further rotation. It can be noted that the clear rack 15 can be shifted manually by means not here pertinent, or by power, as shown in said Patent No. 2,310,281, through the medium of a bar 17. The bar 17 is normally urged to its inoperative, or disengaged, position by :means of a spring 18 tensioned between a stud 19 on the bar 17, and a stud 20 mounted to the carriage frame.

The present invention relates particularly to an improved means for operating the clear bar 17, and for limiting its operation to a single cycle ofthe machine. Operation can be initiated Aby a clearing key, such as key 30 (see Fig. 2). The key 30 is preferably mounted on a stem 31 mounted for substantially vertical sliding movement on the right frame plate 11 by suitable connections such as slots 32 in the key stem 31 embracing pins 33 mounted on the frame plate 11. The key stem 31 also is provided with an aperture 34 which embraces a pin, or stud, 35 mounted on one end of a bellcrank 36. The bellcrank is pivotally mounted on the frame plate 11 by any suitable means, such as shaft 37. A link 38 is pivotally mounted on the lower arm of the bellcrank 36, as by stud, or rivet, 39. The rear end of the link 38 is provided with a slot 40 which embraces a pin, or stud, 45 on bellcrank 46. The link 38 is urged rearwardly in 'the machine by a suitable spring 41 tensioned between a stud on the link 38 and a stud on the frame plate not shown. The urging of the link rearwardly biases the bellcrank 36 in a counterclockwise direction, lifting the key stem 31 and key 30 to their elevated positions shown in Fig. 2.

The bellcrank 46 is pivotally mounted on the right frame plate 11 by any suitable means, such as screw 47, and is adapted to be operated by various mechanisms such as a dividend entry key 48. Thelower arm of the bellcrank 46 carries a stud 49 which engages the upper cam edge of a bellcrank 50 rigidly secured to a transverse shaft 51. Thus, the depression of the clear key 30, through the linkage described, rocks the shaft 51 (clockwise in Fig. 2).

Intermediate the left frame plate 10 and right frame plate 11, the shaft 51 is provided with an arm 55 rigidly secured thereto. This arm 55 supports the forward end of a link 56, the two members being pivotally connected by a suitable stud 57. The rear end of the link 56 is pivotally connected to a shift control arm 66 by any suitable means, such as stud 58. The clear control arm 66 is rigidly secured to a transverse shaft 65 which will be rocked in certain automatic operations when a clearing operation is involved. A pusher arm 67 is also pivotally mounted on the control arm 66 by the stud 5S, the pusher arm extending rearwardly as shown. The pusher 67 is resiliently urged downwardly (clockwise in Fig. 2) by a suitable spring 68 tensioned between a stud on the arm Vand a stud on frame plate 10. The pusher is also provided with 'a suitableshoulder 69 to engage the forward end of a clutch control 'rod 70, as shown in this figure. The clutch control rod 70 is normally urged to its forward, or disengaged, position by a compression spring 74. Thus, the depression of the clear key 3i), or the automatic rocking of shaft 65, is operable to translate the pusher link 67 rearwardly to force the clutch control rod to its operating position, thereby causing engagement of the clear 'clutch 75.

gaged so that the clearing operation is limited to a single machine cycle. This can readily be accomplished by means of a cam 72 rigidly secured to a transverse shaft 73 which is driven in synchronism with the main drive shaft of the calculator. The cam engages a cam follower face 71 on the lower part of. the pusher link 67 whereby the rotation of the shaft 73 lifts the link 67 from engagement with the clutch. control rodv 70, thereby permitting the latter to be biased forwardly by its spring 74.l Thus, operation of the clear-.mechanism is limited to a single machine cycle.

The rearward translation of the clutch control rod 7i?, and consequent engagement of clutch 75, is operative to connect a sleeve Si) to a suitable drive shaft, such as an actuator shaft 76, which is given a full cycle of rotation with each cycle of machine operation. The sleeve 80 is suitably journalled in a rear frame plate 81 and a supporting bracket 82, as shown in both igures. The sleeve 80 carries an integral clear cam 83. A follower roller 84 (see Fig. l) engages the peripheral edge of the cam 83, being rotatably mounted on a clearing arm 85 suitably iournalled between the rear plate-81 and the bracket 82. The arm 85 is resiliently biased into engagement with the cam (clockwise in Fig. l) by a suitable spring'86 tensioned between a stud 87 on the arm and a stud 88 on the rear frame plate 3i., The upper end of the lever 85 is slotted, as at 89, to form a yoke, or Y.

The bifurcation 89 in the upper end of the clearing arm 85 engages a roller 95 mounted on a bellcrank 96. The bellcrank 96 is rockably mounted on a slide 160 by any suitable means, such as stud 103 carried by the slide. The slide 10) is mounted on the rear frame plate 81 for horizontal, or transverse, reciprocation by any suitable means, such as flanged rollers 101. The lower end of the bellcrank 96 is provided with a nose 97 adapted to engage an ear 102 on the slide 100 after slight rocking of the bellc'r'ank 96. The upper arm of the bellcrank 96 is provided with a turned-over ear 98 adapted to engage the edges of notches 110 in a rack member 111 rigidly secured to the clearing bar 17 byvany suitable means such as screws 112. The notches 110 are ordinally spaced along the lower edge of rack 111, whereby the ear 9S of bellcrank 96 will be operative upon the rack 4111 in any ordinal position of the carriage 12.

It will be obvious that the rotation of the cam 83 is operative to first rock the follower arm 85 (counterclockwise in Fig. l) and then to return it to the inoperative'position shown. The rocking of the arm 85 first rocks thebellcrank 96 (clockwise in Fig. l). The bellcrank 96 rocks only slightly until the nose 97 .thereon engages the ear 1.02 of the slide 100, thereby blocking further rocking of the-bellcrank 96. Thereafter the further oscillation of the arm S5 causes the slide-100 to move toward the right of the machine (to theleft in Fig. l) to cause the translation of the rack 111 and the clear operating bar 17 to loperate the clearing mechanism including rack 15. It can also be noted that the initial rocking of the bellcrank 96 is operative to cause engagement of the ear 98 thereon with thev edge' of a notch 110 in the rack 111, thereby enabling the motion of slide 100 to be effectively operative on the rack 111 and slide 17. .The return of the arm 35 and slide v160 to its normal position (tothe right as shown in Fig. l) rocks the bellerank 96=back to its normal position, enabling the ear 98 todrop below'the edge ofthe rack 111, therebydisengaging it from the notch '110 with which it was associated during the clearing operation.

Iclaim: r

1. In a calculating machine vhavinga frame, aregister carriage mounted fortransverse shifting on said frame, a register mounted in said carriage, and means for clearing said register. means for operating said clearing means comprising a drive shaft mounted in said frame, means including a clutch for connecting said means for clearing said register to said drive shaft, and means driven in synchronism with said drive shaft for disengaging said clutch. 2. In a calculating machine having a frame, a register carriage mounted for transverse shifting on said frame, an ordinally arranged register mounted in said carriage, and a reciprocatory means mounted in said carriage for clearing said register, means for operating said clearing means comprising a drive shaft mounted in said frame, a reciprocatory member mounted on said frame, means including a clutch for connecting said reciprocatory memberto said-drive shaft, a member operatively connected to said means for clearing said register and having ordinally arranged projections adapted to be engaged by the reciprocatory member upon operation thereof, and means driven in synchronism with said drive shaft for disengaging said clutch. Y

3. In a calculating machine having a frame, a register carriage mounted for ordinal shifting on said frame, a register mounted in said carriage, and means for clearing said register, means for operating said clearing means in any ordinal position of said carriage comprising, a reciprocatory member mounted on said frame, means for selectively operating said reciprocatory member, a rack having ordinally arranged projections mounted .for reciprocation on said carriage, and Vmeans mounted on said reciprocatory member for engaging the projections on said rack.

4. In a calculating machine having a frame, a register carriage mounted for transverse shifting on said frame, a register mounted in said carriage, and means for clearing said register, means for operating said clearing means comprising a drive shaft mounted on said frame, a reciprocatory member mounted on said frame, means including a displaceable control member for operatively connecting said reciprocatory member to said drive shaft, a rack mounted for reciprocation on said carriage, means mounted on said reciprocatory member for engaging depressions in said rack, a connecting member connecting said rack to said means for clearing said register, and means driven in synchronism with said drive shaft for displacing said displaceable control member from an operative to an inoperative position.

V5. The apparatus of claim 4 wherein the reciprocatory member carries a rocking member mounted for limited rocking thereon, meanscarried by said rocking member for engaging notches in said rack, and means operative to rock said rocking member prior to reciprocation of said rack whereby the member engages the notches of said rack prior to reciprocation ofsaid reciprocat'ory member.

6. In a calculating machine having a frame, a register carriage mounted for transverse shifting on said frame, a register mounted in said carriage, and means for clearing said register, means for operating said clearing means comprising a drive shaft mounted in said frame, a reciprocatory member mounted on said frame, a rocking member mounted for limited rocking on said reciprocatory member, a rack mounted for reciprocation on said carriage, means carried by said rocking member for engaging notches in said rack, means including a displaceable control member for connecting said rocking member to said drive shaft, whereby the member engages the notches of said rack prior to reciprocation of said reciprocatory member, a-connecting member connecting `said rack to' said means for clearing said register, and meanshdriven in. synchronism with said drive shaft-for displacingv said displaceable control member from an operative to an inoperative position.

References Cited in the file of this patent UNITED STATES PATENTS 12,310 281 Friden Feb. 9, 1943 

